


We've Got Chemistry

by iksnilits



Category: Supernatural
Genre: Alternate Universe, Alternate Universe - College/University, Crack, M/M, Sexual Tension, Tutoring
Language: English
Status: Completed
Published: 2013-05-08
Updated: 2013-05-08
Packaged: 2017-12-10 18:49:00
Rating: Not Rated
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,233
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/789047
Author URL: https://archiveofourown.org/users/iksnilits/pseuds/iksnilits
Summary: <blockquote class="userstuff">
              <p>In which Cas is Dean's scheming, sexually frustrating chemistry tutor.</p>
            </blockquote>





	We've Got Chemistry

**Author's Note:**

> Un-beta'd - let me know if you catch any glaring mistakes? 
> 
> Pure indulgence. I love college AUs.

Dean Winchester had a type. And said type was decidedly _not_ rumpled, caffeine-addicted, long-fingered chemistry majors. No, he preferred people that were actually enjoyable to be around. More specifically, people of the cheerleader variety. If you asked him if he was attracted to Castiel Milton, he would deny it vehemently. 

However, Dean was only capable of lying to himself for so long. Two weeks ago, his organic chemistry professor had more or less told him to suck it up and get a tutor or he’d fail his chemistry pre-requisite for his upper-level classes. 

“Here,” Dr. Davis had said. “Call this guy—he’s a bit odd, but he had a 104% in my class last semester and he tutors on Tuesdays and Thursdays. Take care of this before you completely screw yourself over.”

“I appreciate your concern,” Dean had said, and grudgingly made an appointment. 

“For your information, I’m not even getting paid to help you,” Cas said after Dean introduced himself. He leaned back in his library chair, blowing furiously at an uncapped thermos of steaming coffee. “So don’t waste my time. I expect you to come to our sessions prepared. I’ll give you extra worksheets and problems to assess your progress. You’ll report test scores so we can devise lesson material.” 

Dean heard him, but was slightly distracted by the way Cas’s plush lips wrinkled as he pursed them to blow on his coffee. Cas quirked an eyebrow at him, waiting for him to respond. 

“Um. Yes? Yeah. Sounds good. Thanks for doing this, man.” 

Cas grimaced, adjusting his clunky black glasses, and tossed Dean a thick packet of papers. “Do these. It’ll help me see what you’re struggling with.”

It took Dean nearly twice the amount of time it should have to finish Cas’s quiz, because Cas had to catch every drop of coffee that rolled past the rim of his thermos with a swipe of his pink tongue. 

Dean was, apparently, struggling with everything.

“Looks like you’re fine on nomenclature,” Cas said. “That’s good, ‘cause I wouldn’t explain that to you anyway. The rest of it—how are you even passing this class?”

“I’m not,” Dean said. “That’s kind of the problem.”

“Yeah,” Cas sighed, and handed him more papers. “Do these. See you Thursday.”

\---

On Thursday, Cas had a huge cup of hot cocoa in front of him, scooping up dabs of whipped cream with his pointer finger and licking it off as he looked over Dean’s work. 

“Nice,” he said. “But your Williamson Ether Synthesis is shit. You can’t just have things get up and leave, you have to deprotonate the alcohol in the first step—“

Dean tried really, really hard to listen. He really did. But Cas was still eating his whipped cream and sometimes his finger got distracted on the way to his mouth and he’d get the sugar on his lips accidentally; a little cream-white smear that had to be licked off, and after the fifteenth time Cas pulled his finger out of the wet ring of his mouth, Dean wanted to cry. 

“Jesus,” he said. “Can you stop with the slurping and the licking? It’s annoying as fuck.”

“Finish the mechanism and we’ll talk about it,” Cas said, and pushed his whipped-cream laden finger back into his mouth. 

\---

“Benzene rings are supposed to be hexagonal,” Cas said on Tuesday. “Yours look like squares that mated with circles and then did meth for 30 years. You’ll get points deducted if you can’t draw the structures.” 

“I’m not gonna practice drawing shapes,” Dean said. “Seriously, it’s fine.”

Cas sighed, pushing over a sheet of paper. “Try it like this—one continuous line.”

His fingers wrapped around Dean’s, guiding the pencil, and they were bigger and rougher than Dean had expected. Not that he’d thought about Cas’s hands before. Dean found it hard to breathe when Cas pulled his hand away and ran those long fingers up and down the sides of his water bottle, absentmindedly rubbing the condensation around, getting the pads of his fingers all slick and wet. 

“Hexagons,” Dean said dumbly. “Thanks.”

\---

Cas is slumped in his chair, even more disheveled than usual, when Dean arrives the next Thursday. Cas scrolls through his email tiredly, opening one, and groans, dropping his head into his hands. 

“Seriously, fuck _me_ ,” he grits out. 

Dean chokes on his spit and spends a good 20 seconds recovering, blushing furiously. 

“Um. You, ah, you okay?” 

Cas looks up from under his eyelashes and flannel—and the near-exhaustion look should not be as debilitating as it is on Cas. 

“Yes,” Cas sighs, longsufferingly. “I just have to re-submit this application—it’s quite a bit of work I have to do all over again.”

“We don’t have to do this today,” Dean says, and suddenly hopes Cas won’t go. 

“It’s fine,” Cas says. “I might not be of much help, though.”

And he isn’t—but really, Dean wouldn’t know, because Cas keeps yawning and doing full-body stretches that ruck up his paper-thin t-shirt and flash Dean glimpses of some serious abs and those V-shaped sex muscles that dip into his waistband, whatever the fuck they’re called. Dean finds his mouth watering for a taste of the creamy skin rushing under the cotton. 

Cas just rubs his big, flat palm over his chest and down his stomach distractedly as he runs Dean through base-catalyzed epoxide openings, and Dean stumbles back to his room an hour later, half-hard and with no idea of what he was supposed to have learned. 

\---

After four weeks of awkward boners, Dean feels like he’s ready for his next midterm, even if he starts chubbing every time he draws a benzene ring. 

Cas is bending over the counter in the library study room in those tight gray corduroys Dean’s thought of more than once, usually with one hand down his pants and the other fisted in his mouth. Dean forgets what he was going to say, until Cas spins around and grabs the paper out of his hand. 

“How’d you do—whoa, 93%? I must have done something right.” 

Cas grins, and Dean wills his dick to cooperate when Cas takes a step closer. There’s a look in Cas’s eyes that he can’t place—until he’s shoved firmly against the edge of the table and Cas rolls his hips up into Dean’s, pinning him harder. 

“I think a 93 deserves a reward, don’t you?” Cas says, lips brushing Dean’s ear. Dean lets out a moan that he will firmly deny ever making, and finally gets his brain to catch up. 

“What—I mean—you—“

Cas laughs, the bastard. 

“You think all that oral fixation business was for my benefit? I don’t even like whipped cream, Dean.” He punctuates Dean’s name with another hard grind of his hips, and Dean jerks up into him, frantic.

“How ‘bout that reward, huh?”

Cas grins devilishly behind his glasses. “Yeah, alright. I guess I’ll let you suck my cock.”

Dean is later ashamed to admit that he started to drop to his knees right then and there. 

“Jesus, not _now_ ,” Cas hisses. “We’re in a place of _learning_. I see I’ve been wildly successful, however. What say we take this back to my room for some electrophilic addition of our own?”

Dean is too dazed to even call Cas out on his shitty chemistry jokes, and follows him out into the sunshine.


End file.
